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1.
Heliyon ; 10(1): e23822, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192865

RESUMO

A measurement campaign was conducted on San Domino Island, part of the Tremiti Islands archipelago, located in Foggia, Italy. The area is almost entirely covered by vegetation, dominated by the following main species: Juniperus turbinata, Helichrysum italicum, Myrtus communis, Rosmarinus officinalis, Pistacia lentiscus and Pinus halepensis.This study focused on the BVOCs emitted by plants and the ground, employing a simple, economical, and efficient sampling and analysis method. The main known BVOC species emitted by Mediterranean plant species as α-pinene, ß-pinene, camphene and limonene were detected. The measurements highlighted a daily complementarity between plant and soil emissions. The daily variations in BVOCs emitted by both plants and the soil are differ, ensuring an almost constant concentration throughout the day. At the same time, the composition of sea spray aerosol (SSA) was also measured. The measurement sites were selected based on botanical characterization to account for the predominant species on San Domino Island, and the sampling was conducted at human height to accurately identify the species for potential use. The combination of beneficial effects of the substances emitted by plant species and soil, along with the simultaneous presence of SSA, are factors that could enhance the effectiveness of forest therapy in a previously unexplored location.

2.
Small Methods ; 6(12): e2200913, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36333102

RESUMO

Copper sulfide has attracted increasing attention as conversion-type cathode material for, especially, solid-state lithium-based batteries. However, the reaction mechanism behind its extraordinary electroactivity is not well understood, and the various explanations given by the scientific community are diverging. Herein, the CuS reaction dynamics are highlighted by examining the occurring redox processes via a cutting-edge methodology combining X-ray absorption fine structure spectroscopy, and chemometrics to overcome X-ray diffraction limitations posed by the poor material's crystallinity. The mathematical approach rules out the formation of intermediates and clarifies the direct conversion of CuS to Cu in a two-electron process during discharge and reversible oxidation upon delithiation. Two distinct voltage regions are identified corresponding to Cu- as well as the S-redox mechanisms occurring in the material.

3.
J Clin Med ; 11(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142929

RESUMO

Patients undergoing hemodialysis with iron deficiency anemia (IDA) receiving treatment with erythropoiesis-stimulating agents (ESAs) who were intolerant or non-responsive to intravenous (i.v.) ferric gluconate (FG) (hemoglobin; Hb values < 10.5 g/dL or increase in <1 g/dL) or % transferrin saturation; TSAT of <20%) in the previous 6 months were switched to i.v. ferric carboxymaltose (FCM). Changes in iron status parameters, economic and safety measures were also assessed. Seventy-seven hemodialysis patients aged 68 ± 15 years were included. Erythropoietin resistance index decreased from 24.2 ± 14.6 at pre-switch to 20.4 ± 14.6 after 6 months of FCM treatment and Hb levels ≥10.5 g/dL improved from 61% to 75.3% patients (p = 0.042). A 1 g/dL increase in Hb levels was also seen in 26% of patients as well as a 37.7% increase in patients achieving >20% increase in TSAT after FCM. Levels of Hb, TSAT and ferritin parameters increased during FCM treatment with a concomitant decrease in ESA. A mixed-model analysis, which also considered gender, confirmed these trends. Safety variables remained stable, no hypersensitivity reaction was recorded and only one patient reported an adverse event after FCM. FCM treatment was associated with a cost saving of 11.11 EUR/patient/month. These results confirm the efficacy, safety and cost-effectiveness of FCM in correcting IDA in hemodialysis patients.

4.
G Ital Nefrol ; 37(Suppl 75)2020 08 03.
Artigo em Italiano | MEDLINE | ID: mdl-32749086

RESUMO

Intravenous iron supplementation is essential in hemodialysis (HD) patients to recover blood loss and to meet the requirements for erythropoiesis and, in patients receiving erythropoietin, to avert the development of iron deficiency. In a recent real-world study, Hofman et al. showed that a therapeutic shift from iron sucrose (IS) to ferric carboxymaltose (FCM) in HD patients improves iron parameters while reducing use of iron and erythropoietin. The objective of this economic analysis is to compare the weekly cost of treatment of FCM vs IS in hemodialysis patients in Italy. The consumption of drugs (iron and erythropoietin) was derived from Hofman's data, while the value was calculated at Italian ex-factory prices. The analysis was carried on the total patient sample and in two subgroups: patients with iron deficiency and patients anemic at baseline. In addition, specific sensitivity analyses considered prices currently applied at the regional level, simulating the use of IS vs iron gluconate (FG) and epoetin beta vs epoetin alfa. In the base-case analysis, the switch to FCM generates savings of -€12.47 per patient/week (-21%) in all patients, and even greater savings in the subgroups with iron deficiency -€17.28 (-27%) and in anemic patients -€23.08 (-32%). Sensitivity analyses were always favorable to FCM and confirmed the robustness of the analysis. FCM may represent a cost-saving option for the NHS, and Italian real-world studies are needed to quantify the real consumption of resources in dialysis patients.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos Férricos/economia , Compostos Férricos/uso terapêutico , Óxido de Ferro Sacarado/economia , Óxido de Ferro Sacarado/uso terapêutico , Hematínicos/economia , Hematínicos/uso terapêutico , Deficiências de Ferro , Distúrbios do Metabolismo do Ferro/tratamento farmacológico , Maltose/análogos & derivados , Diálise Renal , Humanos , Maltose/economia , Maltose/uso terapêutico
5.
Antioxidants (Basel) ; 9(4)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316684

RESUMO

Chemical and sensory peculiarities of monovarietal extra virgin olive oils (MEVOOs) from the cultivars (cvs.) Ascolana tenera (ASC), Coroncina (COR), Mignola (MIG), Piantone di Mogliano (MOG), and Raggia (RAG) from Marche region (Italy) are investigated. Their polar phenolic substances and α-tocopherol are analysed through high performance liquid chromatography with different detectors. Volatile substances, fatty acid composition, and squalene are analysed by gas chromatography coupled to mass spectrometry (MS) and to the flame ionization detector, respectively. Total antioxidant activity and sensory analysis were also performed. MOG showed high squalene content (on average 0.88 ± 0.16 g/100 g), high relative amount of α-copaene among volatiles, and the highest oleic acid percentage. MIG had high α-tocopherol content (on average 350.0 ± 57.6 mg kg-1) and high α-farnesene in the volatile fraction. ASC showed the highest sensory quality and the lignan pinoresinol with higher concentration as compared to the other MEVOOs (p < 0.05), which resulted in a possible chemical marker for this cv. RAG was characterized by the sensory note of almond, which corresponds to its highest (E)-2-hexenal percentage. Sensory analysis and an antioxidant activity assay performed on a set of industrial extra virgin olive oils purchased in supermarkets, highlighted MEVOOs' superiority from these points of view. Principal component analysis displays the main characteristics of the cvs. investigated.

6.
ChemSusChem ; 13(3): 608-615, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31756022

RESUMO

Manganese hexacyanoferrate (MnHCF) is made of earth-abundant elements by a safe and easy synthesis. The material features a higher specific capacity at a higher potential than other Prussian blue analogs. However, the effect of hydration is critical to determine the electrochemical performance as both the electrochemical behavior and the reaction dynamics are affected by interstitial/structural water and adsorbed water. In this study, the electrochemical activity of MnHCF is investigated by varying the interstitial ion content through a joint operando X-ray absorption spectroscopy and chemometric approach, with the intent to assess the structural and electronic modifications that occur during Na release and Li insertion, as well as the overall dynamic evolution of the system. In MnHCF, both the Fe and Mn centers are electrochemically active and undergo reversible oxidation during the interstitial ion extraction (Fe2+ /Fe3+ and Mn2+ /Mn3+ ). The adsorption of water results in irreversible capacity during charge but only on the Fe site, which is suggested by our chemometric analysis. The local environment of Mn experiences a substantial yet reversible Jahn-Teller effect upon interstitial ion removal because of the formation of trivalent Mn, which is associated with a decrease of the equatorial Mn-N bond lengths by 10 %.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31921822

RESUMO

The final subject position is often the only evidence in the case of the fall of a human being from a given height. Foreseeing the body trajectory and the respective driving force may not be trivial due to the possibility of rotations and to an unknown initial position and momentum of the subject. This article illustrates how multibody models can be used for this aim, with specific reference to an actual case, where a worker fell into a stair well, prior to stair mounting, and he was found in an unexpected posture. The aim of the analysis was establishing if this worker was dead in that same place, if he had been pushed, and which was his initial position. A multibody model of the subject has been built ("numerical android"), given his stature and his known mass. Multiple simulations have been performed, following a design of experiments where various initial positions and velocity as well as pushing forces have been considered, while the objective function to be minimized was the deviation of the numerical android position from the actual worker position. At the end of the analysis, it was possible to point how a very limited set of conditions, all including the application of an external pushing force (or initial speed), could produce the given final posture with an error on the distance function equal to 0.39 m. The full analysis gives a demonstration of the potentiality of multibody models as a tool for the analysis of falls in forensic inquiries.

9.
PLoS One ; 13(4): e0196313, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29702702

RESUMO

BACKGROUND AND AIM OF THE STUDY: In hemodialysis patients, sedentarism is a potentially modifiable mortality risk factor. We explored whether healthcare staff's attitude towards exercise interacts with patient-perceived barriers in modifying the level of physical activity in this population. METHODS: In this prospective, cross-sectional, multicenter study we recruited 608 adult patients and 330 members of the healthcare staff in 16 hemodialysis units in Italy. We assessed patient-perceived barriers to, and healthcare staff's attitude towards, exercise by specific questionnaires. We fitted multilevel linear models to analyze the relationships of either barriers or staff's attitude, and their interaction, with a measure of patient self-reported physical activity (the Human Activity Profile-Adjusted Activity Score [HAP-AAS]), adjusting for multiple confounders. We also employed latent class analysis to dichotomize patients into those endorsing or not endorsing barriers. RESULTS: Most barriers were negatively associated with the HAP-AAS (adjusted change attributable to a given barrier ranging between -5.1 ["Feeling too old", 95% Confidence Interval: -9.4 to -0.8] and -15.6 ["Ulcers on legs and feet", 95%CI: -24.8 to -6.5]. We found a significant interaction between staff's attitude and barriers (adjusted P values ranging between 0.03 ["I do not believe that it is physician's or nurse's role providing advice on exercise to patients on dialysis"] and 0.001 ["I do not often ask patients about exercise"]). A beneficial effect of a proactive staff's attitude was evident only in patients not endorsing barriers. CONCLUSIONS: Barriers and non-proactive staff's attitude reduce physical activity in hemodialysis patients. Patients not endorsing barriers benefit the most from a proactive staff's attitude.


Assuntos
Atitude do Pessoal de Saúde , Exercício Físico , Educação de Pacientes como Assunto/métodos , Diálise Renal , Adulto , Idoso , Estudos Transversais , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Relações Profissional-Paciente , Estudos Prospectivos , Pesquisa Qualitativa , Fatores de Risco
10.
Food Res Int ; 105: 65-75, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433259

RESUMO

The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60-5.90euro/L and 7.49-29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content.


Assuntos
Qualidade dos Alimentos , Azeite de Oliva/análise , Azeite de Oliva/química , Azeite de Oliva/economia , Aldeídos/análise , Antioxidantes/análise , Compostos de Bifenilo/análise , Ácidos Cumáricos/análise , Ácidos Graxos/análise , Humanos , Iridoides/análise , Itália , Olea/química , Azeite de Oliva/classificação , Fenóis/análise , Picratos/análise , Polifenóis/análise , Ácidos Esteáricos/análise , Tocoferóis/análise , alfa-Tocoferol/análise
11.
Blood Purif ; 43(4): 338-345, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28249254

RESUMO

BACKGROUND: Oxidative stress has been related to hypo-response to erythropoiesis-stimulating agents (ESAs) in hemodialysis (HD) patients. The aim of this study was to verify whether vitamin E (ViE) on a synthetic polysulfone dialyzer can improve ESA responsiveness. METHODS: This controlled, multicenter study involved 93 HD patients on stable ESA therapy, who were randomized to either ViE-coated polysulfone dialyzer or to a low-flux synthetic dialyzer. The primary outcome measure was the change in ESA resistance index (ERI) from baseline. RESULTS: Mean ERI decreased in the ViE group by 1.45 IU/kg*g/dl and increased in the control group by 0.53 IU/kg*g/dl, with a mean difference of 1.98 IU/kg*g/dl (p = 0.001 after adjusting for baseline ERI, as foreseen by the study protocol). Baseline ERI was inversely related to its changes during follow-up only in the control group (R2 = 0.29). CONCLUSIONS: The ViE dialyzer can improve ESA response in HD patients. Changes in ERI during follow-up are independent from baseline ERI only in the ViE group. Video Journal Club 'Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=453442.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/administração & dosagem , Membranas Artificiais , Diálise Renal , Vitamina E , Idoso , Anemia/sangue , Anemia/etiologia , Feminino , Seguimentos , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Resultado do Tratamento , Vitamina E/química
12.
Nephrol Dial Transplant ; 30(4): 682-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25385719

RESUMO

BACKGROUND: In haemodialysis (HD) patients, anaemia is associated with reduced survival. Despite treatment with erythropoiesis-stimulating agents (ESAs), a large number of patients with chronic kidney disease show resistance to this therapy and require much higher than usual doses of ESAs in order to maintain the recommended haemoglobin (Hb) target, and recent studies suggest that hepcidin (HEP) may mediate the ESA resistance index (ERI). High-volume online haemodiafiltration (HV-OL-HDF) has been shown to improve anaemia and to reduce the need for ESAs in HD patients; this effect is associated with a reduced inflammatory state in these patients. The aim of the REDERT study (role of haemodiafiltration on ERI) was to investigate the effect of different dialysis techniques on ERI and HEP levels in chronic dialysis patients. METHODS: A single cross-over, randomized, multicentre study (A-B or B-A) was designed. Forty stable HD patients from seven different dialysis units (male 65%, mean age 67.6 ± 14.7 years and mean dialytic age 48 ± 10 months) were enrolled. Patients were randomized to the standard bicarbonate dialysis (BHD) with low-flux polysulfone (PS) membrane group or to the HV-OL-HDF group with high-flux PS membranes and exchange volume of >20 L/session. After 6 months, patients were shifted to the other dialytic group for a further 6 months. Clinical data, Hb, ESA doses and iron metabolism were recorded every month. HEP, beta2-microglobulin (b2MG) and C-reactive protein (CRP) were determined every 3 months, and ERI was calculated monthly as the weekly ESA dose per kilogram of body weight divided by Hb level. Data were analysed using paired-samples t-test, Wilcoxon signed-rank test and Spearman's correlation coefficient. RESULTS: Dialysis efficiency for small molecules assessed as Kt/V was significantly increased in HV-OL-HDF from 1.47 ± 0.24 to 1.49 ± 0.16; P < 0.01. A significant reduction of b2MG was obtained in HV-OL-HDF from month 3 whereas CRP values were not significantly changed during the study period either in BHD or HV-OL-HDF.ERI was significantly reduced in HV-OL-HDF at month 3 and 6 (from 9.1 ± 6.4 UI/weekly/Kg/Hb to 6.7 ± 5.3 UI/weekly/Kg/Hb; P < 0.05) due to a higher ESA consumption in BHD in spite of similar Hb levels. HEP levels were reduced in HV-OL-HDF with respect to BHD after 3 and 6 months. Iron consumption was not significantly different during BHD or HV-OL-HDF treatment as well as transferrin, ferritin and TSAT levels. A significant positive linear correlation between HEP and ERI (r(2) = 0.258, P < 0.001) was observed. CONCLUSIONS: In a uraemic patient population with low-grade inflammation treated with HV-OL-HDF, we observed a significant reduction of ERI values as well as HEP levels. The positive correlation between these two parameters supports a role for HEP in the development of ERI in the dialytic population. Moreover, the lower b2MG and the higher Kt/V achieved in HV-OL-HDF confirms the better depurative effect of this technique in comparison with BHD with respect to middle molecules and small-molecular-weight molecules.


Assuntos
Anemia/tratamento farmacológico , Bicarbonatos/uso terapêutico , Resistência a Medicamentos , Hematínicos/farmacologia , Hemodiafiltração/métodos , Soluções para Hemodiálise/uso terapêutico , Idoso , Proteína C-Reativa/metabolismo , Estudos Cross-Over , Eritropoese/efeitos dos fármacos , Feminino , Hemoglobinas/metabolismo , Hepcidinas/metabolismo , Humanos , Inflamação/tratamento farmacológico , Ferro/metabolismo , Masculino , Sistemas On-Line , Estudos Prospectivos , Uremia/tratamento farmacológico
13.
PLoS One ; 7(11): e48385, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23152771

RESUMO

Glucocorticoids (GCs) such as prednisolone are potent immunosuppressive drugs but suffer from severe adverse effects, including the induction of insulin resistance. Therefore, development of so-called Selective Glucocorticoid Receptor Modulators (SGRM) is highly desirable. Here we describe a non-steroidal Glucocorticoid Receptor (GR)-selective compound (Org 214007-0) with a binding affinity to GR similar to that of prednisolone. Structural modelling of the GR-Org 214007-0 binding site shows disturbance of the loop between helix 11 and helix 12 of GR, confirmed by partial recruitment of the TIF2-3 peptide. Using various cell lines and primary human cells, we show here that Org 214007-0 acts as a partial GC agonist, since it repressed inflammatory genes and was less effective in induction of metabolic genes. More importantly, in vivo studies in mice indicated that Org 214007-0 retained full efficacy in acute inflammation models as well as in a chronic collagen-induced arthritis (CIA) model. Gene expression profiling of muscle tissue derived from arthritic mice showed a partial activity of Org 214007-0 at an equi-efficacious dosage of prednisolone, with an increased ratio in repression versus induction of genes. Finally, in mice Org 214007-0 did not induce elevated fasting glucose nor the shift in glucose/glycogen balance in the liver seen with an equi-efficacious dose of prednisolone. All together, our data demonstrate that Org 214007-0 is a novel SGRMs with an improved therapeutic index compared to prednisolone. This class of SGRMs can contribute to effective anti-inflammatory therapy with a lower risk for metabolic side effects.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Dibenzazepinas/farmacologia , Receptores de Glucocorticoides/agonistas , Tiadiazóis/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/genética , Glicemia , Dibenzazepinas/uso terapêutico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Camundongos , Simulação de Acoplamento Molecular , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Ligação Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Tiadiazóis/uso terapêutico
14.
Int J Artif Organs ; 35(6): 435-43, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22669588

RESUMO

BACKGROUND: Mixed diffusive-convective dialysis therapies offer greater removal capabilities than conventional dialysis. The aim of this study was to compare two different on-line, post-dilution hemodiafiltration (HDF) treatments with regard to achieved convective volume and middle-molecule dialysis efficiency: standard volume control (sOL-HDF) and automated control of the transmembrane pressure (TMP) (UC-HDF). METHODS: We enrolled 30 ESRD patients (55.9 ± 14.0 years, 20/10 M/F) in a randomized, prospective, cross-over study. The patients received a 3-month period of sOL-HDF followed by UC-HDF for a further 3 months, or vice versa, using the same dialysis machine. In sOL-HDF, fixed exchange volumes were set according to a filtration fraction greater than or equal to 25%. In UC-HDF therapy, the exchanged volume was driven by a biofeedback system controlling the TMP and its set point in a double loop. Patients maintained their treatment time, dialyzer, blood flow rate, and anticoagulant regimen unchanged throughout the study. RESULTS: Greater convective volumes were achieved in UC-HDF than in sOL-HDF (23.8 ± 3.9 vs.19.8 ± 4.8 L; p<0.001) with high pre-dialysis Ht value (sOL-HDF 34.0 ± 4.5% and UC-HDF 34.0 ± 4.4%; p = 0.91). The average clearance values of ß2m and P were higher in UC-HDF than in sOL-HDF (respectively 123 ± 24 vs. 111 ± 22 ml/min, p<0.002 and 158 ± 26 vs. 152 ± 25 ml/min, p<0.05). Moreover, the UC-HDF mode led to a significantly increased rate of call-free sessions from 88% to 97% (p<0.0001). CONCLUSIONS: This study showed that the biofeedback module, applied to the automatic control of TMP in on-line HDF, results in higher convective volumes and correspondingly higher ß2m and P clearances. By making the HDF treatment more automated and less complex to perform, it significantly reduced the staff workload.


Assuntos
Hemodiafiltração/métodos , Falência Renal Crônica/terapia , Adulto , Idoso , Anticoagulantes/uso terapêutico , Automação , Biomarcadores/sangue , Estudos Cross-Over , Desenho de Equipamento , Retroalimentação , Feminino , Hemodiafiltração/instrumentação , Hemodiafiltração/enfermagem , Humanos , Itália , Falência Renal Crônica/sangue , Falência Renal Crônica/enfermagem , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Fosfatos/sangue , Pressão , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Carga de Trabalho , Microglobulina beta-2/sangue
15.
G Ital Nefrol ; 29 Suppl 55: S83-8, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-22723148

RESUMO

Paired hemodiafiltration (PHF) is a dialysis modality where an ultrafilter and a filter with hollow-fiber membranes are used in series for on-line infusion of ultrapure fluid. PHF is a on-line hemodiafiltration modality which allows reinfusion using the dialysate prepared by the monitor. The dialysate is infused by retrofiltration, which takes place in the filter positioned in series with regard to the filter where ultrafiltration and the diffusive/convective exchange of solutes occur. The indications and contraindications of the method are the same as those of standard on-line hemodiafiltration, but PHF minimizes the inflammatory response of the patient. This is the result of the increased number of ultrafiltration stages (three), two of which in the monitor and the third by the filter in series, where the retrofiltration takes place. The method can also be carried out with acetate-free dialysate; this reduces the side effects of acetate used to stabilize pH in bicarbonate dialysate, resulting in better cardiovascular stability during dialysis.


Assuntos
Hemodiafiltração/métodos , Hemodiafiltração/instrumentação , Humanos
16.
J Clin Endocrinol Metab ; 97(5): E781-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22419705

RESUMO

The TSH receptor (TSHR) on orbital fibroblasts (OF) is a proposed target of the autoimmune attack in Graves' ophthalmopathy. In the present study, we tested whether the novel low-molecular-weight (LMW) TSHR antagonist Org-274179-0 inhibits cAMP production induced by rhTSH, Graves' disease IgG (GD-IgG), or M22 (a potent human monoclonal TSHR stimulating antibody) in cultured and differentiated OF from Graves' ophthalmopathy patients. cAMP production significantly increased after incubation either with 10 mU/ml rhTSH (3-fold; P ≤ 0.05), 1 mg/ml GD-IgG (2-fold; P ≤ 0.05), or 500 ng/ml M22 (5-fold; P ≤ 0.05). Incubation with the LMW TSHR antagonist dose dependently inhibited rhTSH, GD-IgG as well as the M22-induced cAMP production at nanomolar concentrations; complete blockade was affected at 10(-6) M. Our results suggest that GD-IgG- and M22-induced cAMP production in differentiated OF is exclusively mediated via the TSHR because it can be completely blocked by the LMW TSHR antagonist, Org 274179-0.


Assuntos
Aminoquinolinas/farmacologia , Anticorpos Monoclonais/farmacologia , AMP Cíclico/biossíntese , Fibroblastos/efeitos dos fármacos , Doença de Graves/imunologia , Imunoglobulina G/farmacologia , Receptores da Tireotropina/antagonistas & inibidores , Tireotropina/farmacologia , Animais , Células CHO , Cricetinae , Fibroblastos/metabolismo , Humanos , Órbita/citologia
17.
J Ren Nutr ; 22(6): 541-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22296916

RESUMO

OBJECTIVE: To assess the knowledge of adult hemodialysis patients and nurses working in dialysis units, specifically with regard to knowledge of phosphorus and other nutrients related to dietary management of end-stage renal disease. DESIGN: Cross-sectional cohort study. SETTING: Hemodialysis unit. SUBJECTS: One hundred ninety-one hemodialysis patients and 105 dialysis nurses, as well as 86 control hospital employees who are not health professionals. INTERVENTION: Nutritional knowledge was assessed by a 25-item chronic kidney disease knowledge assessment tool for nutrition, which includes 15 questions on phosphorus and 10 questions on protein, sodium, and potassium knowledge. RESULTS: The scores obtained by patients were much lower than those of nurses (11.6 ± 3.9 vs. 16.0 ± 2.2, P < .001) but slightly higher than those of controls (10.6 ± 3.2, P < .05). Patients with phosphorus serum level >5.5 mg/dL showed chronic kidney disease knowledge assessment tool for nutrition scores similar to those of patients with a serum phosphorus level <5.5 mg/dL. The prevalence of right answers to questions regarding knowledge of phosphorus was lower than that regarding knowledge of the other nutrients, both for patients (38.4% ± 17.8% vs. 57.3% ± 19.9%, P < .001) and nurses (55.6% ± 11.1% vs. 74.8% ± 11.7%, P < .001) as well as for controls (30.7% ± 14.5% vs. 60.1% ± 17.4%, P < .001). CONCLUSIONS: Our study suggests that nutritional knowledge of hemodialysis patients, although higher than the general population, is lower for phosphorus with respect to the other nutrients, such as protein, sodium, and potassium. This occurs even in patients with hyperphosphatemia or those taking phosphate binder medications. Nurses showed the best scores; however, improvement is necessary, especially with regard to knowledge of phosphorus. Training programs on nutrition for nurses and on information for patients should be implemented. They can contribute to achievement of a more effective control of phosphate balance, reduction of costs, and improvement of the quality of care for hemodialysis patients.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Falência Renal Crônica/dietoterapia , Avaliação Nutricional , Estado Nutricional , Fósforo na Dieta/sangue , Diálise Renal , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Br J Pharmacol ; 165(7): 2314-24, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22014107

RESUMO

BACKGROUND AND PURPOSE: Graves' disease (GD) is an autoimmune disease in which the thyroid is overactive, producing excessive amounts of thyroid hormones, caused by thyroid-stimulating hormone (TSH) receptor-stimulating immunoglobulins (TSIs). Many GD patients also suffer from thyroid eye disease (Graves' ophthalmopathy or GO), as TSIs also activate TSH receptors in orbital tissue. We recently developed low molecular weight (LMW) TSH receptor antagonists as a novel therapeutic strategy for the treatment of GD and GO. Here, we determined the molecular pharmacology of a prototypic, nanomolar potent LMW TSH receptor antagonist, Org 274179-0. EXPERIMENTAL APPROACH: Using CHO cells heterogeneously expressing human TSH receptors and rat FRTL-5 cells endogenously expressing rat TSH receptors, we determined the potency and efficacy of Org 274179-0 at antagonizing TSH- and TSI-induced TSH receptor signalling and its cross-reactivity at related follicle-stimulating hormone and luteinizing hormone receptors. We analysed the allosteric mode of interaction of Org 274179-0 and determined whether it is an inverse agonist at five naturally occurring, constitutively active TSH receptor mutants. KEY RESULTS: Nanomolar concentrations of Org 274179-0 completely inhibited TSH (and TSI)-mediated TSH receptor activation with little effect on the potency of TSH, in accordance with an allosteric mechanism of action. Conversely, increasing levels of TSH receptor stimulation only marginally reduced the antagonist potency of Org 274179-0. Org 274179-0 fully blocked the increased basal activity of all the constitutively active TSH receptor mutants tested with nanomolar potencies. CONCLUSIONS AND IMPLICATIONS: Nanomolar potent TSH receptor antagonists like Org 274179-0 have therapeutic potential for the treatment of GD and GO.


Assuntos
Aminoquinolinas/farmacologia , Receptores da Tireotropina/antagonistas & inibidores , Adenilil Ciclases/metabolismo , Aminoquinolinas/química , Animais , Células CHO , Cricetinae , Cricetulus , Avaliação Pré-Clínica de Medicamentos , Doença de Graves/tratamento farmacológico , Doença de Graves/imunologia , Humanos , Peso Molecular , Mutagênese Sítio-Dirigida , Ratos , Receptores da Tireotropina/genética , Receptores da Tireotropina/metabolismo , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Transdução de Sinais/efeitos dos fármacos , Tireotropina/metabolismo
19.
Anal Chem ; 82(9): 3629-35, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20353162

RESUMO

Vanadium pentoxide materials prepared through sol-gel processes act as excellent intercalation hosts for lithium as well as polyvalent cations. A chemometric approach has been applied to study the X-ray absorption near-edge structure (XANES) evolution during in situ scanning of the Cu(0.1)V(2)O(5) xerogel/Li ions battery. Among the more common techniques, the fixed size windows evolving factor analysis (FSWEFA) permits the number of species involved in the experiment to be determined and the range of existence of each of them. This result, combined with the constraints of the invariance of the total concentration and non-negativity of both concentrations and spectra, enabled us to obtain the spectra of the pure components using a multivariate curve resolution refined by an alternate least squares fitting procedure. This allowed the normalized concentration profile to be understood. This data treatment evidenced the occurrence, for the first time, of three species during the battery charging. This fact finds confirmation by comparison of the pure spectra with the experimental ones. Extended X-ray absorption fine structure (EXAFS) analysis confirms the occurrence of three different chemical environments of Cu during battery charging.

20.
J Pharmacol Exp Ther ; 329(2): 783-90, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19190236

RESUMO

The chemokine receptor CXCR2 is involved in different inflammatory diseases, like chronic obstructive pulmonary disease, psoriasis, rheumatoid arthritis, and ulcerative colitis; therefore, it is considered an attractive drug target. Different classes of small CXCR2 antagonists have been developed. In this study, we selected seven CXCR2 antagonists from the diarylurea, imidazolylpyrimide, and thiazolopyrimidine class and studied their mechanisms of action at human CXCR2. All compounds are able to displace (125)I-CXCL8 and inhibit CXCL8-induced beta-arrestin2 recruitment. Detailed studies with representatives of each class showed that these compounds displace and antagonize CXCL8, most probably via a noncompetitive, allosteric mechanism. In addition, we radiolabeled the high-affinity CXCR2 antagonist SB265610 [1-(2-bromophenyl)-3-(4-cyano-1H-benzo[d] [1,2,3]-triazol-7-yl)urea] and subjected [(3)H]SB265610 to a detailed analysis. The binding of this radioligand was saturable and reversible. Using [(3)H]SB265610, we found that compounds of the different chemical classes bind to distinct binding sites. Hence, the use of a radiolabeled low-molecular weight CXCR2 antagonist serves as a tool to investigate the different binding sites of CXCR2 antagonists in more detail.


Assuntos
Compostos de Fenilureia/farmacologia , Receptores de Interleucina-8B/antagonistas & inibidores , Sítio Alostérico , Animais , Ligação Competitiva , Células COS , Chlorocebus aethiops , Humanos , Compostos de Fenilureia/química , Ligação Proteica , Ensaio Radioligante , Relação Estrutura-Atividade , Transfecção
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